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1.
J Antimicrob Chemother ; 79(4): 810-814, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38366372

RESUMEN

OBJECTIVES: An Escherichia coli isolate, WGS1363, showed resistance to piperacillin/tazobactam but susceptibility to cephalosporins and contained a previously unrecognized ß-lactamase, CTX-M-255, as the only acquired ß-lactamase. CTX-M-255 was identical to CTX-M-27 except for a G239S substitution. Here, we characterize the hydrolytic spectrum of CTX-M-255 and a previously reported ß-lactamase, CTX-M-178, also containing a G239S substitution and compare it to their respective parental enzymes, CTX-M-27 and CTX-M-15. METHODS: All ß-lactamase genes were expressed in E. coli TOP10 and MICs to representative ß-lactam-antibiotics were determined. Furthermore, blaCTX-M-15,  blaCTX-M-27, blaCTX-M-178 and blaCTX-M-255 with C-terminal His-tag fusions were affinity purified for enzyme kinetic assays determining Michaelis-Menten kinetic parameters against representative ß-lactam-antibiotics and IC50s of clavulanate, sulbactam, tazobactam and avibactam. RESULTS: TOP10-transformants expressing blaCTX-M-178 and blaCTX-M-255 showed resistance to penicillin/ß-lactamase combinations and susceptibility to cephalothin and cefotaxime in contrast to transformants expressing blaCTX-M-15 and blaCTX-M-27. Determination of enzyme kinetic parameters showed that CTX-M-178 and CTX-M-255 both lacked hydrolytic activity against cephalosporins and showed impaired hydrolytic efficiency against penicillin antibiotics compared to their parental enzymes. Both enzymes appeared more active against piperacillin compared to benzylpenicillin and ampicillin. Compared to their parental enzymes, IC50s of ß-lactamase-inhibitors were increased more than 1000-fold for CTX-M-178 and CTX-M-255. CONCLUSIONS: CTX-M-178 and CTX-M-255, both containing a G239S substitution, conferred resistance to piperacillin/tazobactam and may be characterized as inhibitor-resistant CTX-M ß-lactamases. Inhibitor resistance was accompanied by loss of activity against cephalosporins and monobactams. These findings add to the necessary knowledge base for predicting antibiotic susceptibility from genotypic data.


Asunto(s)
Antibacterianos , Inhibidores de beta-Lactamasas , Inhibidores de beta-Lactamasas/farmacología , Antibacterianos/farmacología , Escherichia coli , beta-Lactamasas/genética , Penicilinas/farmacología , Cefalosporinas/farmacología , Tazobactam/farmacología , Piperacilina/farmacología , Monobactamas , Combinación Piperacilina y Tazobactam , Pruebas de Sensibilidad Microbiana
3.
Phys Chem Chem Phys ; 26(14): 10998-11013, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38526443

RESUMEN

The presence of amyloid fibrils is a hallmark of several neurodegenerative diseases. Some amyloidogenic proteins, such as α-synuclein and amyloid ß, interact with lipids, and this interaction can strongly favour the formation of amyloid fibrils. In particular the primary nucleation step, i.e. the de novo formation of amyloid fibrils, has been shown to be accelerated by lipids. However, the exact mechanism of this acceleration is still mostly unclear. Here we use a range of scattering methods, such as dynamic light scattering (DLS) and small angle X-ray and neutron scattering (SAXS and SANS) to obtain structural information on the binding of α-synuclein to model membranes formed from negatively charged lipids and their co-assembly into amyloid fibrils. We find that the model membranes take an active role in the reaction. The binding of α synuclein to the model membranes immediately induces a major structural change in the lipid assembly, which leads to a break-up into small and mostly disc- or rod-like lipid-protein particles. This transition can be reversed by temperature changes or proteolytic protein removal. Incubation of the small lipid-α-synuclein particles for several hours, however, leads to amyloid fibril formation, whereby the lipids are incorporated into the amyloid fibrils.


Asunto(s)
Péptidos beta-Amiloides , alfa-Sinucleína , alfa-Sinucleína/química , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Amiloide/química , Lípidos
4.
Nord J Psychiatry ; 78(4): 328-338, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38436663

RESUMEN

PURPOSE: To explore mental health staff's responses towards interventions designed to reduce the use of mechanical restraint (MR) in adult mental health inpatient settings. METHODS: We conducted a cross-sectional, questionnaire-based survey. The questionnaire, made available online via REDCap, presented 20 interventions designed to reduce MR use. Participants were asked to rate and rank the interventions based on their viewpoints regarding the relevance and importance of each intervention. RESULTS: A total of 128 mental health staff members from general and forensic mental health inpatient units across the Mental Health Services in the Region of Southern Denmark completed the questionnaire (response rate = 21.3%). A total of 90.8% of the ratings scored either 'agree' (45.2%) or 'strongly agree' (45.6%) concerning the relevance of the interventions in reducing MR use. Overall and in the divided analysis, interventions labelled as 'building relationship' and 'patient-related knowledge' claimed high scores in the staff's rankings of the interventions' importance concerning implementation. Conversely, interventions like 'carers' and 'standardised assessments' received low scores. CONCLUSIONS: The staff generally considered that the interventions were relevant. Importance rankings were consistent across the divisions chosen, with a range of variance and dispersion being recorded among certain groups.


Asunto(s)
Actitud del Personal de Salud , Pacientes Internos , Restricción Física , Humanos , Restricción Física/estadística & datos numéricos , Adulto , Estudios Transversales , Masculino , Femenino , Encuestas y Cuestionarios , Dinamarca , Pacientes Internos/psicología , Trastornos Mentales/terapia , Trastornos Mentales/psicología , Persona de Mediana Edad , Hospitales Psiquiátricos , Servicios de Salud Mental
5.
Nord J Psychiatry ; 78(5): 448-455, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38626028

RESUMEN

INTRODUCTION: Even if coercive measures are widely applied in psychiatry and have numerous well-known drawbacks, there is limited known on the agreement among mental healthcare professionals' opinions on their use. In a questionnaire study using standardized scenarios, we investigated variation in staff opinions on coercion. METHODS: In a web-based survey distributed to staff at three psychiatry hospitals, respondents were asked to consider if and what coercion to use by introducing two hypothetical scenarios involving involuntary psychiatric admission and in-hospital coercion. RESULTS: One hundred thirty-two out of 601 invited staff members responded to the survey (Response Rate = 22%). There was large variation in participating staff members' opinions on how to best manage critical situations and what coercive measures were warranted. In the first scenario, 57% of respondents (n = 76) believed that the patient should be involuntarily admitted to hospital while the remaining respondents believed that the situation should be managed otherwise. Regarding the second scenario, 62% of respondents responded that some in-hospital coercion should be used. The majority of respondents believed that colleagues would behave similarly (60%) or with a tendency towards more coercion use (34%). Male gender, being nursing staff and having less coercion experience predicted being less inclined to choose involuntary hospital admission. CONCLUSION: There is a high degree of variation in coercion use. This study suggests that this variation persists despite staff members being confronted with the same standardized situations. There is a need for evidence-based further guidance to minimize coercion in critical mental healthcare situations.


Asunto(s)
Actitud del Personal de Salud , Coerción , Internamiento Obligatorio del Enfermo Mental , Humanos , Masculino , Femenino , Adulto , Encuestas y Cuestionarios , Persona de Mediana Edad , Hospitales Psiquiátricos/estadística & datos numéricos , Trastornos Mentales/terapia , Trastornos Mentales/psicología
6.
Am J Hematol ; 98(3): 388-397, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36588403

RESUMEN

Peripheral T-Cell Lymphomas (PTCLs) are rare, aggressive lymphomas with poor outcomes, but limited-stage disease is infrequent and not well-described. This study reports outcomes and prognostic factors in limited-stage nodal PTCLs in a binational population-based setting. Patients were identified from the Danish and Swedish lymphoma registries. Adults diagnosed with limited-stage nodal PTCL (stage I-II) and treated with CHOP(-like) therapy ±radiotherapy between 2000 and 2014 were included. Medical records were reviewed by local investigators. A total of 239 patients with a median age of 62 years were included; 67% received 6-8 cycles of CHOP(-like) therapy and 22% received 3-4 cycles, of which 59% also received radiotherapy. Autologous stem cell transplant consolidation was administered to 16% of all patients. Median follow-up was 127 months with 5-years overall survival (OS) of 58% (95% CI: 53-65) and progression-free survival (PFS) of 53% (95% CI: 47-59). In multivariable analysis, age ≥ 60 years and B-symptoms were unfavorable and ALK+ anaplastic large cell T-Cell lymphoma was favorable for survival outcomes. There was no difference in treatment-specific outcome (3-4 cycles vs. 6-8 cycles of CHOP(-like) ± radiotherapy). Low-risk patients (age < 60 without B-symptoms) had a 5-year OS of 77% (95% CI 67-89%). In the present study of limited-stage nodal PTCL, survival after curative intent chemotherapy +/- radiotherapy was inferior to that of limited-stage diffuse large B-cell lymphoma, but a subgroup of young patients without B-symptoms had very good outcomes. Treatment outcomes after 3-4 cycles versus 6-8 cycles of CHOP(-like) therapy were comparable.


Asunto(s)
Linfoma de Células B Grandes Difuso , Linfoma Anaplásico de Células Grandes , Linfoma de Células T Periférico , Adulto , Humanos , Persona de Mediana Edad , Linfoma de Células T Periférico/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Resultado del Tratamiento , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Trasplante de Células Madre , Doxorrubicina , Prednisona/efectos adversos , Vincristina , Ciclofosfamida
7.
Soft Matter ; 19(8): 1586-1595, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36749349

RESUMEN

Nature employs an impressive range of topologically complex ordered nanostructures that occur in various forms in both natural and synthetic materials. A particular class of these exhibits negative curvature and forms periodic saddle-shaped surfaces in three dimensions. Unlike pattern formation on flat or positively curved surfaces like spherical systems, the understanding of patterning on such surfaces is highly complicated due to the structures being intrinsically intertwined in three dimensions. We present a new method for visualisation and analysis of patterns on triply periodic negatively curved surfaces by mapping to two-dimensional hyperbolic space analogous to spherical projections in cartography thus effectively creating a more accessible "hyperbolic map" of the pattern. Specifically, we exemplify the method via the simplest triply periodic minimal surfaces: the Primitive, Diamond, and Gyroid in their universal cover along with decorations from a soft materials, whose structures involve decorations of soft matter on negatively curved surfaces, not necessarily minimal.

8.
Org Biomol Chem ; 21(45): 8993-9004, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37869763

RESUMEN

2A-F,3B,C,E,F,6B,C,E,F-Tetradeca-O-benzyl-α-cyclodextrin or Ling's tetrol is a unique α-cyclodextrin derivative that is partially protected with specific access points on both rims of the cyclodextrin structure. Ling's tetrol is therefore potentially useful for the synthesis of more complex and sophisticated enzyme models and supramolecular structures. However, the original synthesis gave only 10% yield after a reaction time of 4 days, and a recent improvement that gave 52% yield required two steps and a reaction time in one step of 6 days. Here, a single-step synthesis is reported where Ling's tetrol is obtained in a yield of 59% with a reaction time of 40 hours. 2A-F,3B,C,E,F,6B,C,E,F-Tetradeca-O-benzyl-α-cyclodextrin was subsequently converted into 6A,D-dicarboxy-3A,D-diepi-α-cyclodextrin, 3A,D-dioxo-α-cyclodextrin and 3A,D-diamino-3A,D-dideoxy-3A,D-diepi-α-cyclodextrin. The binding of these compounds to CH4 and CO2 was determined.

9.
Soc Psychiatry Psychiatr Epidemiol ; 58(4): 505-522, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36454269

RESUMEN

PURPOSE: To identify and summarise extant knowledge about patient ethnicity and the use of various types of restrictive practices in adult mental health inpatient settings. METHODS: A scoping review methodological framework recommended by the JBI was used. A systematic search was conducted in APA PsycINFO, CINAHL with Full Text, Embase, PubMed and Scopus. Additionally, grey literature searches were conducted in Google, OpenGrey and selected websites, and the reference lists of included studies were explored. RESULTS: Altogether, 38 studies were included: 34 were primary studies; 4, reviews. The geographical settings were as follows: Europe (n = 26), Western Pacific (n = 8), Americas (n = 3) and South-East Asia (n = 1). In primary studies, ethnicity was reported according to migrant/national status (n = 16), mixed categories (n = 12), indigenous vs. non-indigenous (n = 5), region of origin (n = 1), sub-categories of indigenous people (n = 1) and religion (n = 1). In reviews, ethnicity was not comparable. The categories of restrictive practices included seclusion, which was widely reported across the studies (n = 20), multiple restrictive practices studied concurrently (n = 17), mechanical restraint (n = 8), rapid tranquillisation (n = 7) and manual restraint (n = 1). CONCLUSIONS: Ethnic disparities in restrictive practice use in adult mental health inpatient settings has received some scholarly attention. Evidence suggests that certain ethnic minorities were more likely to experience restrictive practices than other groups. However, extant research was characterised by a lack of consensus and continuity. Furthermore, widely different definitions of ethnicity and restrictive practices were used, which hampers researchers' and clinicians' understanding of the issue. Further research in this field may improve mental health practice.


Asunto(s)
Pacientes Internos , Salud Mental , Adulto , Humanos , Etnicidad , Europa (Continente) , Restricción Física
10.
Beilstein J Org Chem ; 19: 1021-1027, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37497051

RESUMEN

Carbon dioxide (CO2) emissions from industrial processes, power generation, and transportation contribute significantly to global warming and climate change. Carbon capture and storage (CCS) technologies are essential to reduce these emissions and mitigate the effects of climate change. Cyclodextrins (CDs), cyclic oligosaccharides, are studied as potential CO2 capture agents due to their unique molecular structures and high selectivity towards CO2. In this paper we have investigated binding efficiency of a number of cyclodextrins towards CO2. It is found that the crystal structure of α-cyclodextrin with CO2 has a 1:1 stoichioimetry and that a number of simple and modified cyclodextrins bind CO2 in water with a Kg of 0.18-1.2 bar-1 (7-35 M-1) with per-O-methyl α-cyclodextrin having the highest CO2 affinity.

11.
Gut ; 71(3): 627-642, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-33833066

RESUMEN

OBJECTIVE: HCV-genotype 4 infections are a major cause of liver diseases in the Middle East/Africa with certain subtypes associated with increased risk of direct-acting antiviral (DAA) treatment failures. We aimed at developing infectious genotype 4 cell culture systems to understand the evolutionary genetic landscapes of antiviral resistance, which can help preserve the future efficacy of DAA-based therapy. DESIGN: HCV recombinants were tested in liver-derived cells. Long-term coculture with DAAs served to induce antiviral-resistance phenotypes. Next-generation sequencing (NGS) of the entire HCV-coding sequence identified mutation networks. Resistance-associated substitutions (RAS) were studied using reverse-genetics. RESULT: The in-vivo infectious ED43(4a) clone was adapted in Huh7.5 cells, using substitutions identified in ED43(Core-NS5A)/JFH1-chimeric viruses combined with selected NS5B-changes. NGS, and linkage analysis, permitted identification of multiple genetic branches emerging during culture adaptation, one of which had 31 substitutions leading to robust replication/propagation. Treatment of culture-adapted ED43 with nine clinically relevant protease-DAA, NS5A-DAA and NS5B-DAA led to complex dynamics of drug-target-specific RAS with coselection of genome-wide substitutions. Approved DAA combinations were efficient against the original virus, but not against variants with RAS in corresponding drug targets. However, retreatment with glecaprevir/pibrentasvir remained efficient against NS5A inhibitor and sofosbuvir resistant variants. Recombinants with specific RAS at NS3-156, NS5A-28, 30, 31 and 93 and NS5B-282 were viable, but NS3-A156M and NS5A-L30Δ (deletion) led to attenuated phenotypes. CONCLUSION: Rapidly emerging complex evolutionary landscapes of mutations define the persistence of HCV-RASs conferring resistance levels leading to treatment failure in genotype 4. The high barrier to resistance of glecaprevir/pibrentasvir could prevent persistence and propagation of antiviral resistance.


Asunto(s)
Antivirales/farmacología , Farmacorresistencia Viral/genética , Hepacivirus/efectos de los fármacos , Hepacivirus/fisiología , Hepatocitos/virología , Mutación/genética , Bencimidazoles/farmacología , Técnicas de Cultivo de Célula , Combinación de Medicamentos , Genotipo , Hepacivirus/genética , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Humanos , Pirrolidinas/farmacología , Quinoxalinas/farmacología , Sofosbuvir/farmacología , Sulfonamidas/farmacología
12.
Am J Transplant ; 22(11): 2637-2650, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35801693

RESUMEN

Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has been associated with a high risk of adverse outcomes in solid organ transplant (SOT) recipients in the pre-vaccination era. In this retrospective cohort study, we examined the incidence and severity of COVID-19 in kidney and liver transplant recipients in Denmark in the post-vaccination era, from December 27, 2020, to December 27, 2021. We included 1428 SOT recipients with 143 cases of first-positive SARS-CoV-2 PCR test. The cumulative incidence of first-positive SARS-CoV-2 PCR test 1 year after initiation of vaccination was 10.4% (95% CI: 8.8-12.0), and the incidence was higher in kidney than in liver transplant recipients (11.6% [95% CI: 9.4-13.8] vs. 7.4% [95% CI: 5.1-9.8], p = .009). After the first-positive SARS-CoV-2 PCR test, the hospitalization rate was 31.5% (95% CI: 23.9-39.1), and 30-day all-cause mortality was 3.7% (95% CI: 0.5-6.8). Hospitalization was lower in vaccinated than in unvaccinated SOT recipients (26.4% [95% CI: 18.1-34.6] vs. 48.5% [95% CI: 31.4-65.5], p = .011), as was mortality (1.8% [95% CI: 0.0-4.3] vs. 9.1% [95% CI: 0.0-18.9], p = .047). In conclusion, SOT recipients remain at high risk of adverse outcomes after SARS-CoV-2 infections, with a lower risk observed in vaccinated than in unvaccinated SOT recipients.


Asunto(s)
COVID-19 , Trasplante de Riñón , Trasplante de Órganos , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Incidencia , Estudios Retrospectivos , Trasplante de Riñón/efectos adversos , Trasplante de Órganos/efectos adversos , Receptores de Trasplantes , Vacunación , Hígado , Dinamarca/epidemiología
13.
Appl Environ Microbiol ; 88(19): e0108722, 2022 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-36165644

RESUMEN

Synbiotics combine probiotics and prebiotics and are being investigated for potential health benefits. In this single-group-design trial, we analyzed changes in the gut microbiome, stool quality, and gastrointestinal well-being in 15 healthy volunteers after a synbiotic intervention comprising Lacticaseibacillus rhamnosus (LGG), Lactobacillus acidophilus (LA-5), Lacticaseibacillus paracasei subsp. paracasei (L. CASEI 431), and Bifidobacterium animalis subsp. lactis BB-12 and 20 g of chicory-derived inulin powder consumed daily for 4 weeks. Fecal samples were collected at baseline and at completion of the intervention, and all participants completed a fecal diary based on the Bristol Stool Scale and recorded their gastrointestinal well-being. No adverse effects were observed after consumption of the synbiotic product, and stool consistency and frequency remained almost unchanged during the trial. Microbiome analysis of the fecal samples was achieved using shotgun sequencing followed by taxonomic profiling. No changes in alpha and beta diversity were seen after the intervention. Greater relative abundances of Bifidobacteriaceae were observed in 12 subjects, with indigenous bifidobacteria species constituting the main increase. All four probiotic organisms increased in abundance, and L. rhamnosus, B. animalis, and L. acidophilus were differentially abundant, compared to baseline. Comparison of the fecal strains to the B. animalis subsp. lactis BB-12 reference genome and the sequenced symbiotic product revealed only a few single-nucleotide polymorphisms differentiating the probiotic B. animalis subsp. lactis BB-12 from the fecal strains identified, indicating that this probiotic strain was detectable after the intervention. IMPORTANCE The effects of probiotics/synbiotics are seldom investigated in healthy volunteers; therefore, this study is important, especially considering the safety aspects of multiple probiotics together with prebiotic fiber in consumption by humans. The study explores at the potential of a synbiotic intervention with lactobacilli, bifidobacteria, and inulin in healthy volunteers and tracks the ingested probiotic strain B. animalis subsp. lactis.


Asunto(s)
Bifidobacterium animalis , Probióticos , Simbióticos , Humanos , Bifidobacterium , Heces/microbiología , Voluntarios Sanos , Inulina , Lactobacillus , Lactobacillus acidophilus , Prebióticos , Probióticos/farmacología
14.
Opt Lett ; 47(19): 5172-5175, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36181214

RESUMEN

We report on a fiber-based chirped-pulse-amplification laser system with bulk transmission grating compression to a pulse duration of 357 fs, average power of 175 W, and pulse energy of 233µ J. The compressed pulse train has a beam quality factor M2 of 1.21. The power amplifier is based on a state-of-the-art single-mode photonic crystal rod-type ytterbium-doped fiber operating at 248 W of average power and a repetition rate of 750 kHz. The long-term stability of the laser system has been tested continuously for more than 4000 hours and shows no sign of transverse mode instability.

15.
Euro Surveill ; 27(10)2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35272746

RESUMEN

Following emergence of the SARS-CoV-2 variant Omicron in November 2021, the dominant BA.1 sub-lineage was replaced by the BA.2 sub-lineage in Denmark. We analysed the first 2,623 BA.2 cases from 29 November 2021 to 2 January 2022. No epidemiological or clinical differences were found between individuals infected with BA.1 versus BA.2. Phylogenetic analyses showed a geographic east-to-west transmission of BA.2 from the Capital Region with clusters expanding after the Christmas holidays. Mutational analysis shows distinct differences between BA.1 and BA.2.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Dinamarca/epidemiología , Humanos , Epidemiología Molecular , Filogenia , SARS-CoV-2/genética
16.
Antimicrob Agents Chemother ; 65(7): e0009721, 2021 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-33903110

RESUMEN

Efforts to mitigate the coronavirus disease 2019 (COVID-19) pandemic include the screening of existing antiviral molecules that could be repurposed to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Although SARS-CoV-2 replicates and propagates efficiently in African green monkey kidney (Vero) cells, antivirals such as nucleos(t)ide analogs (NUCs) often show decreased activity in these cells due to inefficient metabolization. SARS-CoV-2 exhibits low viability in human cells in culture. Here, serial passages of a SARS-CoV-2 isolate (original-SARS2) in the human hepatoma cell clone Huh7.5 led to the selection of a variant (adapted-SARS2) with significantly improved infectivity in human liver (Huh7 and Huh7.5) and lung cancer (unmodified Calu-1 and A549) cells. The adapted virus exhibited mutations in the spike protein, including a 9-amino-acid deletion and 3 amino acid changes (E484D, P812R, and Q954H). E484D also emerged in Vero E6-cultured viruses that became viable in A549 cells. Original and adapted viruses were susceptible to scavenger receptor class B type 1 (SR-B1) receptor blocking, and adapted-SARS2 exhibited significantly less dependence on ACE2. Both variants were similarly neutralized by COVID-19 convalescent-phase plasma, but adapted-SARS2 exhibited increased susceptibility to exogenous type I interferon. Remdesivir inhibited original- and adapted-SARS2 similarly, demonstrating the utility of the system for the screening of NUCs. Among the tested NUCs, only remdesivir, molnupiravir, and, to a limited extent, galidesivir showed antiviral effects across human cell lines, whereas sofosbuvir, ribavirin, and favipiravir had no apparent activity. Analogously to the emergence of spike mutations in vivo, the spike protein is under intense adaptive selection pressure in cell culture. Our results indicate that the emergence of spike mutations will most likely not affect the activity of remdesivir.


Asunto(s)
COVID-19 , SARS-CoV-2 , Antivirales/farmacología , Chlorocebus aethiops , Humanos , Pandemias , Glicoproteína de la Espiga del Coronavirus , Replicación Viral
17.
J Viral Hepat ; 28(2): 302-316, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33131178

RESUMEN

Direct-acting antivirals (DAAs) have proven highly effective against chronic hepatitis C virus (HCV) infection. However, some patients experience treatment failure, associated with resistance-associated substitutions (RASs). Our aim was to investigate the complete viral coding sequence in hepatitis C patients treated with DAAs to identify RASs and the effects of treatment on the viral population. We selected 22 HCV patients with sustained virologic response (SVR) to match 21 treatment-failure patients in relation to HCV genotype, DAA regimen, liver cirrhosis and previous treatment experience. Viral-titre data were compared between the two patient groups, and HCV full-length open reading frame deep-sequencing was performed. The proportion of HCV NS5A-RASs at baseline was higher in treatment-failure (82%) than matched SVR patients (25%) (p = .0063). Also, treatment failure was associated with slower declines in viraemia titres. Viral population diversity did not differ at baseline between SVR and treatment-failure patients, but failure was associated with decreased diversity probably caused by selection for RAS. The NS5B-substitution 150V was associated with sofosbuvir treatment failure in genotype 3a. Further, mutations identified in NS2, NS3-helicase and NS5A-domain-III were associated with DAA treatment failure in genotype 1a patients. Six retreated HCV patients (35%) experienced 2nd treatment failure; RASs were present in 67% compared to 11% with SVR. In conclusion, baseline RASs to NS5A inhibitors, but not virus population diversity, and lower viral titre decline predicted HCV treatment failure. Mutations outside of the DAA targets can be associated with DAA treatment failure. Successful DAA retreatment in patients with treatment failure was hampered by previously selected RASs.


Asunto(s)
Antivirales , Hepatitis C Crónica , Antivirales/farmacología , Antivirales/uso terapéutico , Farmacorresistencia Viral/genética , Quimioterapia Combinada , Genotipo , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Retratamiento , Insuficiencia del Tratamiento , Proteínas no Estructurales Virales/genética
18.
Blood ; 134(24): 2159-2170, 2019 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-31562134

RESUMEN

Peripheral T-cell lymphoma (PTCL) is a heterogeneous group of mature T-cell malignancies; approximately one-third of cases are designated as PTCL-not otherwise specified (PTCL-NOS). Using gene-expression profiling (GEP), we have previously defined 2 major molecular subtypes of PTCL-NOS, PTCL-GATA3 and PTCL-TBX21, which have distinct biological differences in oncogenic pathways and prognosis. In the current study, we generated an immunohistochemistry (IHC) algorithm to identify the 2 subtypes in paraffin tissue using antibodies to key transcriptional factors (GATA3 and TBX21) and their target proteins (CCR4 and CXCR3). In a training cohort of 49 cases of PTCL-NOS with corresponding GEP data, the 2 subtypes identified by the IHC algorithm matched the GEP results with high sensitivity (85%) and showed a significant difference in overall survival (OS) (P = .03). The IHC algorithm classification showed high interobserver reproducibility among pathologists and was validated in a second PTCL-NOS cohort (n = 124), where a significant difference in OS between the PTCL-GATA3 and PTCL-TBX21 subtypes was confirmed (P = .003). In multivariate analysis, a high International Prognostic Index score (3-5) and the PTCL-GATA3 subtype identified by IHC were independent adverse predictors of OS (P = .0015). Additionally, the 2 IHC-defined subtypes were significantly associated with distinct morphological features (P < .001), and there was a significant enrichment of an activated CD8+ cytotoxic phenotype in the PTCL-TBX21 subtype (P = .03). The IHC algorithm will aid in identifying the 2 subtypes in clinical practice, which will aid the future clinical management of patients and facilitate risk stratification in clinical trials.


Asunto(s)
Biomarcadores de Tumor , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/etiología , Adulto , Anciano , Algoritmos , Biología Computacional/métodos , Femenino , Perfilación de la Expresión Génica , Humanos , Inmunohistoquímica , Inmunofenotipificación , Linfoma de Células T Periférico/metabolismo , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Reproducibilidad de los Resultados
19.
Blood ; 133(15): 1664-1676, 2019 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-30782609

RESUMEN

Peripheral T-cell lymphoma (PTCL) is a group of complex clinicopathological entities, often associated with an aggressive clinical course. Angioimmunoblastic T-cell lymphoma (AITL) and PTCL-not otherwise specified (PTCL-NOS) are the 2 most frequent categories, accounting for >50% of PTCLs. Gene expression profiling (GEP) defined molecular signatures for AITL and delineated biological and prognostic subgroups within PTCL-NOS (PTCL-GATA3 and PTCL-TBX21). Genomic copy number (CN) analysis and targeted sequencing of these molecular subgroups revealed unique CN abnormalities (CNAs) and oncogenic pathways, indicating distinct oncogenic evolution. PTCL-GATA3 exhibited greater genomic complexity that was characterized by frequent loss or mutation of tumor suppressor genes targeting the CDKN2A /B-TP53 axis and PTEN-PI3K pathways. Co-occurring gains/amplifications of STAT3 and MYC occurred in PTCL-GATA3. Several CNAs, in particular loss of CDKN2A, exhibited prognostic significance in PTCL-NOS as a single entity and in the PTCL-GATA3 subgroup. The PTCL-TBX21 subgroup had fewer CNAs, primarily targeting cytotoxic effector genes, and was enriched in mutations of genes regulating DNA methylation. CNAs affecting metabolic processes regulating RNA/protein degradation and T-cell receptor signaling were common in both subgroups. AITL showed lower genomic complexity compared with other PTCL entities, with frequent co-occurring gains of chromosome 5 (chr5) and chr21 that were significantly associated with IDH2 R172 mutation. CN losses were enriched in genes regulating PI3K-AKT-mTOR signaling in cases without IDH2 mutation. Overall, we demonstrated that novel GEP-defined PTCL subgroups likely evolve by distinct genetic pathways and provided biological rationale for therapies that may be investigated in future clinical trials.


Asunto(s)
Variaciones en el Número de Copia de ADN , Linfoma de Células T Periférico/genética , Oncogenes , Femenino , Factor de Transcripción GATA3/genética , Perfilación de la Expresión Génica , Humanos , Linfadenopatía Inmunoblástica/genética , Linfoma de Células T Periférico/clasificación , Masculino , Mutación , Proteínas de Dominio T Box/genética
20.
Chemistry ; 27(1): 316-325, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-32955737

RESUMEN

Functional pairing between cellular glycoconjugates and tissue lectins like galectins has wide (patho)physiological significance. Their study is facilitated by nonhydrolysable derivatives of the natural O-glycans, such as S- and Se-glycosides. The latter enable extensive analyses by specific 77 Se NMR spectroscopy, but still remain underexplored. By using the example of selenodigalactoside (SeDG) and the human galectin-1 and -3, we have evaluated diverse 77 Se NMR detection methods and propose selective 1 H,77 Se heteronuclear Hartmann-Hahn transfer for efficient use in competitive NMR screening against a selenoglycoside spy ligand. By fluorescence anisotropy, circular dichroism, and isothermal titration calorimetry (ITC), we show that the affinity and thermodynamics of SeDG binding by galectins are similar to thiodigalactoside (TDG) and N-acetyllactosamine (LacNAc), confirming that Se substitution has no major impact. ITC data in D2 O versus H2 O are similar for TDG and LacNAc binding by both galectins, but a solvent effect, indicating solvent rearrangement at the binding site, is hinted at for SeDG and clearly observed for LacNAc dimers with extended chain length.


Asunto(s)
Galectinas , Resonancia Magnética Nuclear Biomolecular , Polisacáridos , Sitios de Unión , Óxido de Deuterio , Galectinas/metabolismo , Humanos , Isótopos , Ligandos , Polisacáridos/metabolismo , Unión Proteica , Selenio , Solventes
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